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• Intro / Home
• Historical Neighbors
• Street and Backyard

• Park and Green Places

• Shore and Wetlands

• Salt and Freshwater

• Tiny Neighbors
• Unwelcome Neighbors
• Occasional and
  Unexpected Neighbors

• Wildlife Sighting Log
• Resources

• Hours and Tours


 Unwelcome Neighbors  
Unwelcome intro | Image: 1. 2. 3. 4. 5.

This rogues’ gallery of unwelcome wildlife includes rats, mice, cockroaches, fleas, bedbugs, lice, ticks, destructive moth species, tree borers, House Flies, mosquitoes, and shipworms: creatures for whom no one, or hardly anyone, has a good word. Excluded from this inventory are pigeons, House Sparrows, and Starlings, since these often reviled birds do have legions of defenders and admirers.

Some "unwelcome neighbors" are annoying pests, some can spread potentially deadly diseases, some wreak environmental damage, and some weaken and even destroy urban structures. "Unwelcome," rather than "bad," is used here to describe these pests because, although they are certainly "bad" for people, these animals, like all other creatures (including humans), seek only to live their lives and reproduce. Each successful species finds its special niche; unfortunately for us, our bodies, our foods, our domestic animals, our homes, our crops, and our cities supply the wherewithal for many creatures to thrive.

Animal pests tend to be tough survivors, and attempts at their total eradication are usually fruitless. Cockroaches develop immunity to pesticides, and indiscriminate spraying kills not only mosquitoes but also many inoffensive insects. Even biological approaches, such as the introduction of an alien predator to control a specific pest, can have an impact on other species in disastrous and unforeseen ways.

It may be some consolation to know that animal pests must contend with animal predators of their own. The notorious Oriental Rat Flea, transmitter of plague, feeds not only on human blood, but also on that of its host, the rat. And fleas have their own problems, as the satirist Jonathan Swift commented in 1733:

So, naturalists observe, a flea
Has smaller fleas that on him prey;
And these have smaller still to bite ’em;
And so proceed ad infinitum....

Check out the sighting log to record your interaction with some of the native New York City wildlife featured in Urban Neighbors. You may also browse the sighting log by animal, borough, park or natural area, and/or habitat to view a sighting you have submitted or to read others’ observations.




Norway Rat / NYPL


Cockroach / NYPL


Mosquito / NYPL

Common Shipworm / NYPL


House Fly / NYPL

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